perf tools: Add dedicated unwind addr_space member into thread struct

Milian reported issue with thread::priv, which was double booked by perf
trace and DWARF unwind code. So using those together is impossible at
the moment.

Moving DWARF unwind private data into separate variable so perf trace
can keep using thread::priv.

Reported-and-Tested-by: Milian Wolff <milian.wolff@kdab.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andreas Hollmann <hollmann@in.tum.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1460013073-18444-2-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h
index a0ac0317affb5ffc46f69dc00c4c258d0c40c684..e214207bb13ac67df5a3c48bc379b1b65e583f75 100644 (file)
--- a/tools/perf/util/thread.h
+++ b/tools/perf/util/thread.h
@@ -9,6 +9,9 @@
 #include "symbol.h"
 #include <strlist.h>
 #include <intlist.h>
+#ifdef HAVE_LIBUNWIND_SUPPORT
+#include <libunwind.h>
+#endif
 
 struct thread_stack;
 
@@ -32,6 +35,9 @@ struct thread {
 
        void                    *priv;
        struct thread_stack     *ts;
+#ifdef HAVE_LIBUNWIND_SUPPORT
+       unw_addr_space_t        addr_space;
+#endif
 };
 
 struct machine;

diff --git a/tools/perf/util/unwind-libunwind.c b/tools/perf/util/unwind-libunwind.c
index ee7e372297e59adb7eb3c7a1ffec8acb6186f704..63687d3a344e7f39b94f465547e929b2c2779b40 100644 (file)
--- a/tools/perf/util/unwind-libunwind.c
+++ b/tools/perf/util/unwind-libunwind.c
@@ -32,6 +32,7 @@
 #include "symbol.h"
 #include "util.h"
 #include "debug.h"
+#include "asm/bug.h"
 
 extern int
 UNW_OBJ(dwarf_search_unwind_table) (unw_addr_space_t as,
@@ -580,43 +581,33 @@ static unw_accessors_t accessors = {
 
 int unwind__prepare_access(struct thread *thread)
 {
-       unw_addr_space_t addr_space;
-
        if (callchain_param.record_mode != CALLCHAIN_DWARF)
                return 0;
 
-       addr_space = unw_create_addr_space(&accessors, 0);
-       if (!addr_space) {
+       thread->addr_space = unw_create_addr_space(&accessors, 0);
+       if (!thread->addr_space) {
                pr_err("unwind: Can't create unwind address space.\n");
                return -ENOMEM;
        }
 
-       unw_set_caching_policy(addr_space, UNW_CACHE_GLOBAL);
-       thread__set_priv(thread, addr_space);
-
+       unw_set_caching_policy(thread->addr_space, UNW_CACHE_GLOBAL);
        return 0;
 }
 
 void unwind__flush_access(struct thread *thread)
 {
-       unw_addr_space_t addr_space;
-
        if (callchain_param.record_mode != CALLCHAIN_DWARF)
                return;
 
-       addr_space = thread__priv(thread);
-       unw_flush_cache(addr_space, 0, 0);
+       unw_flush_cache(thread->addr_space, 0, 0);
 }
 
 void unwind__finish_access(struct thread *thread)
 {
-       unw_addr_space_t addr_space;
-
        if (callchain_param.record_mode != CALLCHAIN_DWARF)
                return;
 
-       addr_space = thread__priv(thread);
-       unw_destroy_addr_space(addr_space);
+       unw_destroy_addr_space(thread->addr_space);
 }
 
 static int get_entries(struct unwind_info *ui, unwind_entry_cb_t cb,
@@ -639,7 +630,9 @@ static int get_entries(struct unwind_info *ui, unwind_entry_cb_t cb,
         * unwind itself.
         */
        if (max_stack - 1 > 0) {
-               addr_space = thread__priv(ui->thread);
+               WARN_ONCE(!ui->thread, "WARNING: ui->thread is NULL");
+               addr_space = ui->thread->addr_space;
+
                if (addr_space == NULL)
                        return -1;